Case Description—An 8-month-old crossbred dog was evaluated because of an oronasal fistula following 2 previous attempts to surgically correct a secondary palate defect.
Clinical Findings—Three months after initial evaluation and successful closure of the soft palate section of the secondary palate defect via 2 surgeries, an oronasal fistula was present. The oronasal fistula was predominantly right sided, involving the rostral third of the hard palate and, at the widest aspect, spanning the transverse palate at the level of the maxillary canine teeth.
Treatment and Outcome—Following CT of the rostral aspect of the skull, rapid prototyping technology was used to create a stereolithographic model of the skull, allowing fabrication of a customized titanium plate for intranasal stenting. The titanium plate was inserted via a rostral nasal approach and secured rostrally with 1.5-mm screws and caudally with 2.4-mm screws from the nasal bridge. An oronasal fistula formed laterally at the edge of the plate, but bonding of a dental glass ionomer product resulted in successful resolution of the fistula.
Clinical Relevance—Results suggested that rapid prototyping and creation of customized implants may provide an option for the management of large or nonreconstructible oronasal defects in dogs.
CASE DESCRIPTION A 13-year-old neutered male Abyssinian cat with a 4-month history of right forelimb edema and multifocal crusting lesions at the distal aspect of the antebrachium was referred to a veterinary teaching hospital for evaluation. Extensive hemorrhage from the lesions had been observed after self-grooming, and findings on histologic examination of a skin biopsy sample prior to referral were consistent with atypical dermal hemodynamics and inflammation.
CLINICAL FINDINGS Diffuse pitting edema and multifocal, 3- to 4-mm-diameter sanguineous crusting lesions affecting the antebrachium were observed distal to a pulsatile subcutaneous mass in the right elbow joint region that had a palpable thrill and auscultable bruit. No systemic abnormalities were detected.
TREATMENT AND OUTCOME Contrast-enhanced CT angiography with 3-D reconstruction identified an arteriovenous fistula with a large aberrant vessel coursing distally. Surgical ligation of an arterialized vein distal to the fistula without en bloc resection led to resolution of all clinical signs. The vascular anomaly was no longer patent when diagnostic imaging was repeated 5 months after surgery.
CLINICAL RELEVANCE Acquired arteriovenous fistulas can lead to bleeding skin lesions affecting the antebrachium in cats. Surgical ligation of an aberrant reverse-shunting vein distal to the fistula successfully resolved clinical signs in the cat of this report and may warrant investigation as a treatment option in cats with this condition.
Objective—To develop an in vivo CT method to measure inclination angles and motion of the sacroiliac joints in dogs of performance breeds.
Animals—10 German Shepherd Dogs and 12 Greyhounds without signs of lumbosacral region pain or neurologic problems.
Procedures—CT of the ilium and sacrum was performed in flexed, neutral, and extended hind limb positions. Lines were drawn on volume-rendered images acquired in the flexed and extended positions to measure motion of the ilia relative to the sacra. Inclination angles of the synovial and ligamentous components of the sacroiliac joints were measured on transverse-plane CT images acquired at cranial and caudal locations. Coefficients of variance of measurements were calculated to determine intraobserver variability.
Results—Coefficients of variance of measurements ranged from 0.17% to 2.45%. A significantly higher amount of sacroiliac joint rotational motion was detected for German Shepherd Dogs versus Greyhounds. The cranial synovial joint component had a significantly more sagittal orientation in German Shepherd Dogs versus Greyhounds. No significant differences were detected between breeds for x- or y-axis translational motion or caudal synovial or ligamentous joint component inclination angles.
Conclusions and Clinical Relevance—The small amounts of sacroiliac joint motion detected in this study may buffer high-frequency vibrations during movement of dogs. Differences detected between breeds may be associated with the predisposition of German Shepherd Dogs to develop lumbosacral region signs of pain, although the biological importance of this finding was not determined. Future studies are warranted to compare sacroiliac joint variables between German Shepherd Dogs with and without lumbosacral region signs of pain.
OBJECTIVE To characterize the processes involved in and outcomes achieved with custom-designed patient-specific implants to provide functional replacement of skeletal structures in dogs with tumors of the mandible, radius, or tibia.
DESIGN Prospective case series.
ANIMALS 6 dogs with mandibular tumors, 5 with tumors of the distal aspect of the radius, and 1 with a tumor in the distal aspect of the tibia treated from June 2013 to September 2016 at 3 referral centers.
PROCEDURES After tumor staging, implants were designed from patients' CT scans by means of various computer-aided design applications and printed by means of selective laser melting in titanium-6 aluminum-4 vanadium alloy. A cutting jig was created in thermoplastic to ensure each osteotomy was performed as planned. Following ostectomy, the implant was secured into the defect with screws of appropriate size and length.
RESULTS Initial return to normal clinical function was good to excellent for 11 of the 12 dogs. However, major complications resulted in revision of the implant or amputation of the limb in 5 dogs, and at least 3 of these complications were considered a consequence of faulty implant design or manufacturing. Infection developed in 2 dogs and was successfully treated in 1 dog. The longest-surviving dog maintained good limb function for 2 years.
CONCLUSIONS AND CLINICAL RELEVANCE This is the largest reported series of dogs managed with customized 3-D-printed titanium implants. The 3-D printing allowed complex and patient-specific 3-D geometries to be fabricated, enabling function-sparing treatment of bone cancer affecting multiple anatomic sites.